Ancient Sigil - Timeline Question

I'm working on an adventure which features a set of sensory stones containing memories of several defining events of Sigils past. I still have difficulties to place two events, though:
The Clueless Rebellion and the Mazing of the Communals.

Well, we know (or at least suspect) that Ravel Puzzlewell was involved with the Clueless Rebellion, and that she was mazed at the end of it.

At least, that's my assumption. The portals were opened during the rebellion with the Shadow-Sorcelled Key, and Ravel "kept herself alive with shadow magic." The leader of the rebellion was almost certainly the Nameless One, and who else would he have turned to to craft such a key? Who else could have done it? We know that when Ravel came to Sigil, "she almost undid the Cage itself."

We know Kesai-Serris is Ravel's daughter, so perhaps, assuming Ravel obeys linear logic, Kesai-Serris must have been born before the Clueless Rebellion. But Ravel has other aspects in other planes, and it's not necessarily her caged self that birthed Kesai-Serris. We don't know how old Kesai-Serris is anyway; she's half night hag and half cambion, so there's no clear upper limit to her lifespan.

Ravel once destroyed a Guvner with shadows for daring to quote Sigilian law to her, so unless the Guvner visited her maze, the Clueless Rebellion must have happened while the Fraternity of Order existed. So that's less than 855 years before Hashkar.

Faction War, though, says that the Sodkillers and Incanterium were extant when the Clueless Rebellion happened, so it must have been before the Great Upheaval. That narrows things down to between 855 and 504 years before Hashkar's reign (which is where you placed it on your list anyway, so).

This is also roughly the era that Chapter VII of Dead Gods takes place in, but we don't have any precise dates for that either. So probably the best idea is to put it smack dab in the middle of the range, 688 years before Hashkar.

I have the Communals vanishing circa -373 Hashkar, but I'm honestly not sure where I got the number. The idea was that the remaining Communals joined either the Free League or one of two other factions. Those for whom radical egalitarianism was a way of empowering themselves as individuals joined Rillith's Collector's Society to form the even more radical Sign of One faction, which preached that not only were each of them equal to the gods and the Lady of Pain, but each of them—or one of them, as some of them believed—had created the entire multiverse. Those for whom the Communals had been a way of reforming society joined Yr Nial's Order of Dis school (a Xaositect predecessor) to become the Ochlocrats (another Xaositect predecessor), which preached that rule by oligarchs be replaced with rule by the mob, the most democratic and common part of society, because all other forms of government ultimately decayed into autocracies, meritocracies, oligarchies, and kleptocracies.